New Mexico State Senator William Sharer has introduced legislation aimed at altering the state's constitution to define marriage as a heterosexual union.

Sharer filed his bill Thursday in reaction to a New Mexico Supreme Court ruling legalizing gay marriage in the state.

(Related: New Mexico: 17th state to legalize gay marriage.)

Sharer led the legal effort to uphold an interpretation of the state's marriage laws that excludes gay and lesbian couples.

The Republican lawmaker told ABC Albuquerque affiliate KOAT that he drafted the proposed amendment before the court issued its ruling.

“I had it drafted weeks ago and it was just sitting there waiting until I said go,” Sharer said. “[Gay marriage opponents] need to get on the phone and start calling and emailing their legislators.”

“My constituents are very much in favor of marriage as has been known in every culture, on every continent, in every era. And that's between one man and one woman,” he added.

While reiterating her opposition to marriage equality, Republican Governor Susana Martinez called for unity following the court's decision.

“As we move forward, I am hopeful that we will not be divided, as we must come together to tackle very pressing issues,” she said in a statement.

Sharer introduced a similar unsuccessful measure in 2011.

(Related: New Mexico GOPer William Sharer: Gay men should stop “whoring,” marry women.)